import gulp from 'gulp'
import loadPlugins from 'gulp-load-plugins'
import del from 'del'
import glob from 'glob'
import path from 'path'
import { Instrumenter } from 'isparta'
import webpack from 'webpack'
import webpackStream from 'webpack-stream'
// import source from 'vinyl-source-stream'

import mochaGlobals from './test/setup/.globals'
import manifest from './package.json'

// Load all of our Gulp plugins
const $ = loadPlugins()

// Gather the library data from `package.json`
const config = manifest.babelBoilerplateOptions
const mainFile = manifest.main
const destinationFolder = path.dirname(mainFile)
const exportFileName = path.basename(mainFile, path.extname(mainFile))

function cleanDist (done) {
  del([destinationFolder]).then(() => done())
}

function cleanTmp (done) {
  del(['tmp']).then(() => done())
}

function onError () {
  $.util.beep()
}

// Lint a set of files
function lint (files) {
  return gulp.src(files)
    .pipe($.plumber())
    .pipe($.eslint())
    .pipe($.eslint.format())
    .pipe($.eslint.failOnError())
    // .pipe($.jscs())
    // .pipe($.jscs.reporter('fail'))
    .on('error', onError)
}

function lintSrc () {
  return lint('src/**/*.js')
}

function lintTest () {
  return lint('test/**/*.js')
}

function lintGulpfile () {
  return lint('gulpfile.babel.js')
}

function build () {
  return gulp.src(path.join('src', config.entryFileName + '.js'))
    .pipe($.plumber())
    .pipe(webpackStream({
      output: {
        filename: exportFileName + '.js',
        libraryTarget: 'umd',
        library: config.mainVarName
      },
      module: {
        loaders: [
          { test: /\.js$/, exclude: /node_modules/, loader: 'babel-loader' }
        ]
      },
      devtool: 'source-map'
    }))
    .pipe(gulp.dest(destinationFolder))
    .pipe($.filter(['*', '!**/*.js.map']))
    .pipe($.rename(exportFileName + '.min.js'))
    .pipe($.sourcemaps.init({ loadMaps: true }))
    .pipe($.uglify())
    .pipe($.sourcemaps.write('./'))
    .pipe(gulp.dest(destinationFolder))
}

function _mocha () {
  return gulp.src(['test/setup/node.js', 'test/unit/**/*.js'], {read: false})
    .pipe($.mocha({
      reporter: 'dot',
      globals: Object.keys(mochaGlobals.globals),
      ignoreLeaks: false
    }))
}

function _registerBabel () {
  require('babel-register')
}

function test () {
  _registerBabel()
  return _mocha()
}

function coverage (done) {
  _registerBabel()
  gulp.src(['src/**/*.js'])
    .pipe($.istanbul({ instrumenter: Instrumenter }))
    .pipe($.istanbul.hookRequire())
    .on('finish', () => {
      return test()
        .pipe($.istanbul.writeReports())
        .on('end', done)
    })
}

const watchFiles = ['src/**/*', 'test/**/*', 'package.json', '**/.eslintrc', '.jscsrc']

// Run the headless unit tests as you make changes.
function watch () {
  gulp.watch(watchFiles, ['test'])
}

function testBrowser () {
  // Our testing bundle is made up of our unit tests, which
  // should individually load up pieces of our application.
  // We also include the browser setup file.
  const testFiles = glob.sync('./test/unit/**/*.js')
  const allFiles = ['./test/setup/browser.js'].concat(testFiles)

  // Lets us differentiate between the first build and subsequent builds
  var firstBuild = true

  // This empty stream might seem like a hack, but we need to specify all of our files through
  // the `entry` option of webpack. Otherwise, it ignores whatever file(s) are placed in here.
  return gulp.src('')
    .pipe($.plumber())
    .pipe(webpackStream({
      watch: true,
      entry: allFiles,
      output: {
        filename: '__spec-build.js'
      },
      module: {
        loaders: [
          // This is what allows us to author in future JavaScript
          { test: /\.js$/, exclude: /node_modules/, loader: 'babel-loader' },
          // This allows the test setup scripts to load `package.json`
          { test: /\.json$/, exclude: /node_modules/, loader: 'json-loader' }
        ]
      },
      plugins: [
        // By default, webpack does `n=>n` compilation with entry files. This concatenates
        // them into a single chunk.
        new webpack.optimize.LimitChunkCountPlugin({ maxChunks: 1 })
      ],
      devtool: 'inline-source-map'
    }, null, function () {
      if (firstBuild) {
        $.livereload.listen({port: 35729, host: 'localhost', start: true})
        gulp.watch(watchFiles, ['lint'])
      } else {
        $.livereload.reload('./tmp/__spec-build.js')
      }
      firstBuild = false
    }))
    .pipe(gulp.dest('./tmp'))
}
function style () {
  return gulp.src('demo/css/*.css')
   .pipe($.concatCss('piano.css'))
   .pipe(gulp.dest('build/'))
}

function server () {
  gulp.src('demo')
    .pipe($.webserver({
      livereload: true,
      fallback: 'index.html',
      open: true,
      port: 8080
    }))
  gulp.watch(path.join('src/', config.entryFileName + '.js'), ['dev-build'])
  console.log('Watching File : src/', config.entryFileName + '.js')
}

function develop () {
  gulp.src(path.join('src/', config.entryFileName + '.js'))
  .pipe($.plumber())
  .pipe(webpackStream({
    output: {
      filename: exportFileName + '.js',
      libraryTarget: 'umd',
      library: config.mainVarName
    },
    module: {
      loaders: [
        { test: /\.js$/, exclude: /node_modules/, loader: 'babel-loader' }
      ]
    },
    devtool: 'source-map'
  }))
  .pipe(gulp.dest('./demo/dist'))
}
// Remove the built files
gulp.task('clean', cleanDist)

// Remove our temporary files
gulp.task('clean-tmp', cleanTmp)

// Lint our source code
gulp.task('lint-src', lintSrc)

// Lint our test code
gulp.task('lint-test', lintTest)

// Lint this file
gulp.task('lint-gulpfile', lintGulpfile)

// Lint everything
gulp.task('lint', ['lint-src', 'lint-test', 'lint-gulpfile'])

// Build two versions of the library
gulp.task('build', ['lint', 'clean', 'style'], build)

gulp.task('style', style)
// Lint and run our tests
gulp.task('test', ['lint'], test)

// Set up coverage and run tests
gulp.task('coverage', ['lint'], coverage)

// Set up a livereload environment for our spec runner `test/runner.html`
gulp.task('test-browser', ['lint', 'clean-tmp'], testBrowser)

// develop
gulp.task('develop', ['server'], develop)

// webpack
gulp.task('server', server)

//dev-build
gulp.task('dev-build', develop)

// Run the headless unit tests as you make changes.
gulp.task('watch', watch)

// An alias of test
gulp.task('default', ['test'])
